请问怎么用ClientSocket控件实现HTTP的GET方法?

Question

例如我要访问“http://www.baidu.com/home.html”这个页面应该怎么构造封包呢？

Answer 1

参考：http://blog.csdn.net/unsigned/archive/2008/09/22/2960982.aspx

Answer 2

也可以用现成的组件，如TIdHTTP来实现。

Answer 3

up unsigned blog
http://blog.csdn.net/unsigned/archive/2008/09/22/2960982.aspx

Answer 4

用的办法可以，不过需要自己组装HTTP，可以使用一些现成的控件，下面是一些方法，HTTP: THTTPSend你可以换成INDY的HTTP控件function HttpGetText(const URL: string; const Response: TStrings; HeaderList: string): Boolean;
var
  HTTP: THTTPSend;
begin
  HTTP := THTTPSend.Create;
  try
    if HeaderList <> '' then
      HTTP.Headers.Add(HeaderList);
    Result := HTTP.HTTPMethod('GET', URL);
    Response.LoadFromStream(HTTP.Document);
  finally
    HTTP.Free;
  end;
end;function HttpGetText(const URL: string; const Response: TStrings;
  const ProxyHost, ProxyPort: string; HeaderList: string): Boolean; overload;
var
  HTTP: THTTPSend;
begin
  HTTP := THTTPSend.Create;
  try
    HTTP.ProxyHost := ProxyHost;
    HTTP.ProxyPort := ProxyPort;
    if HeaderList <> '' then
      HTTP.Headers.Add(HeaderList);
    Result := HTTP.HTTPMethod('GET', URL);
    Response.LoadFromStream(HTTP.Document);
  finally
    HTTP.Free;
  end;
end;function HttpGetBinary(const URL: string; const Response: TStream; HeaderList: string): Boolean;
var
  HTTP: THTTPSend;
begin
  HTTP := THTTPSend.Create;
  try
    if HeaderList <> '' then
      HTTP.Headers.Add(HeaderList);
    Result := HTTP.HTTPMethod('GET', URL);
    Response.Seek(0, soFromBeginning);
    Response.CopyFrom(HTTP.Document, 0);
  finally
    HTTP.Free;
  end;
end;function HttpGetBinary(const URL: string; const Response: TStream;
  const ProxyHost, ProxyPort: string; HeaderList: string): Boolean; overload;
var
  HTTP: THTTPSend;
begin
  Result := False;
  HTTP := THTTPSend.Create;
  try
    HTTP.ProxyHost := ProxyHost;
    HTTP.ProxyPort := ProxyPort;
    if HeaderList <> '' then
      HTTP.Headers.Add(HeaderList);
    Result := HTTP.HTTPMethod('GET', URL);
    Response.Seek(0, soFromBeginning);
    Response.CopyFrom(HTTP.Document, 0);
  finally
    HTTP.Free;
  end;
end;function HttpPostBinary(const URL: string; const Data: TStream): Boolean;
var
  HTTP: THTTPSend;
begin
  HTTP := THTTPSend.Create;
  try
    HTTP.Document.CopyFrom(Data, 0);
    HTTP.MimeType := 'Application/octet-stream';
    Result := HTTP.HTTPMethod('POST', URL);
    Data.Seek(0, soFromBeginning);
    Data.CopyFrom(HTTP.Document, 0);
  finally
    HTTP.Free;
  end;
end;function HttpPostURL(const URL, URLData: string; const Data: TStream): Boolean;
var
  HTTP: THTTPSend;
begin
  HTTP := THTTPSend.Create;
  try
    HTTP.Document.Write(Pointer(URLData)^, Length(URLData));
    HTTP.MimeType := 'application/x-www-form-urlencoded';
    Result := HTTP.HTTPMethod('POST', URL);
    Data.CopyFrom(HTTP.Document, 0);
  finally
    HTTP.Free;
  end;
end;function HttpPostURL(const URL, URLData: string; const Data: TStream;
  const AProxySvr, AProxyPrt: string): Boolean;
var
  HTTP: THTTPSend;
begin
  HTTP := THTTPSend.Create;
  try
    HTTP.ProxyHost := AProxySvr;
    HTTP.ProxyPort := AProxyPrt;
    HTTP.Document.Write(Pointer(URLData)^, Length(URLData));
    HTTP.MimeType := 'application/x-www-form-urlencoded';
    Result := HTTP.HTTPMethod('POST', URL);
    Data.CopyFrom(HTTP.Document, 0);
  finally
    HTTP.Free;
  end;
end;function HttpPostURL(const URL, URLData: string; var Data: string): Boolean; overload;
var
  AData: TMemoryStream;
  slRet: TStringList;
begin
  AData := TMemoryStream.Create;
  try
    Result := HttpPostURL(URL, URLData, AData);
    if Result then
    begin
      slRet := TStringList.Create;
      try
        AData.Position := 0;
        slRet.LoadFromStream(AData);
        Data := slRet.Text;
      finally
        slRet.Free;
      end;
    end;
  finally
    AData.Free;
  end;
end;function HttpPostURL(const URL, URLData: string; var Data: string;
  const AProxySvr, AProxyPrt: string): Boolean; overload;
var
  AData: TMemoryStream;
  slRet: TStringList;
begin
  AData := TMemoryStream.Create;
  try
    Result := HttpPostURL(URL, URLData, AData, AProxySvr, AProxyPrt);
    if Result then
    begin
      slRet := TStringList.Create;
      try
        AData.Position := 0;
        slRet.LoadFromStream(AData);
        Data := slRet.Text;
      finally
        slRet.Free;
      end;
    end;
  finally
    AData.Free;
  end;
end;function HttpPostFile(const URL, FieldName, FileName: string;
  const Data: TStream; const ResultData: TStrings): Boolean;
var
  HTTP: THTTPSend;
  Bound, s: string;
begin
  Bound := IntToHex(Random(MaxInt), 8) + '_Synapse_boundary';
  HTTP := THTTPSend.Create;
  try
    s := '--' + Bound + CRLF;
    s := s + 'content-disposition: form-data; name="' + FieldName + '";';
    s := s + ' filename="' + FileName +'"' + CRLF;
    s := s + 'Content-Type: Application/octet-string' + CRLF + CRLF;
    HTTP.Document.Write(Pointer(s)^, Length(s));
    HTTP.Document.CopyFrom(Data, 0);
    s := CRLF + '--' + Bound + '--' + CRLF;
    HTTP.Document.Write(Pointer(s)^, Length(s));
    HTTP.MimeType := 'multipart/form-data; boundary=' + Bound;
    Result := HTTP.HTTPMethod('POST', URL);
    ResultData.LoadFromStream(HTTP.Document);
  finally
    HTTP.Free;
  end;
end;

Answer 5

CLIENTSOCKET连接成功后会调用一次ONWRITE事件,在ONWRITE事件中构建完整的HTTP头,发送给对方就可以,HTTP头可以用抓包软件抓IE的第一个包看看.之后就是ONREAD直到下载完ONDISCONNECT